Rugby: All Blacks coach Steve Hansen refusing to give up on Sonny Bill Williams for 2019 Rugby World Cup

Sonny Bill Williams will soon be back for the Blues. Photo / Getty

If there is one area that will have the All Blacks selectors asking hard questions of themselves before the Rugby World Cup it is the midfield, with coach Steve Hansen yesterday confirming Sonny Bill Williams will be given every opportunity to prove his fitness and form.

Blues second-five Williams hasn't played since hurting his right knee in his team's victory over the Stormers at Eden Park six weeks ago. He subsequently had surgery on a cartilage problem, and while the 33-year-old's rugby days are probably nearly numbered as a result of that long-running injury issue, as well as others, Williams' quality and experience in playing 51 tests cannot be denied.

Williams is back running and Hansen believes he will be back playing within a couple of weeks – which means he will probably miss the Blues' crunch derby against the Crusaders in Christchurch on Saturday.

The naysayers will have it that Williams is running out of time, but if he can put together a few good games for the Blues before the season is out he will be selected for the Rugby Championship squad in early July and then it's game on for the World Cup should he do enough and remain healthy.

"I understand why people would say he's running out of time," Hansen said. "But is he really? He's already proved himself - he's played how many tests? 50? That's a lot of tests and that's a lot of proving.

"What we need to see is him back on the track and then we have to ask is his fitness good enough to be selected in a team that has five tests before the World Cup. Does he deserve to show us whether he's good enough? Of course he does, because he's played 50 test matches.

"All those boys who have played in the midfield will get an opportunity to show us that they're good enough. In the end, personally I think they all are."

In an interesting aside as he prepared to lead his squad of North Island All Blacks, plus the injured Owen Franks and Ben Smith, in a foundation day in south Auckland, Hansen said the selectors would likely pick only three or four midfielders in their World Cup squad of 31.

It's doubtful they will take only three, even with the relatively short travel distance from New Zealand to Japan (a 12-hour flight) in the event of an injury. They are more likely to go for four.

If Williams is fit and playing anywhere near his potential he is a shoo-in for the squad, so with Jack Goodhue, Ryan Crotty and Anton Lienert-Brown also almost guaranteed to attend if fit, the major casualty could be the Hurricanes' Ngani Laumape. Likewise, Ma'a Nonu's hopes probably rest on at least one injury.

The selectors will name a big squad to prepare for the tests against Argentina in Buenos Aires on July 21 and South Africa in Wellington six days later. The Super Rugby final will be held on July 6 and Hansen confirmed few All Blacks involved in that would travel to play the Pumas. That could rule out quite a few Crusaders as they remain on track to appear in their third consecutive title.

"That means we'll have to take a few extra players for those first two games and that will be fine because it gives us an opportunity to see them in our environment and playing footy in some cases," Hansen said.

A smaller squad will be named for the two Bledisloe Cup tests against Australia in Perth on August 10 and Eden Park a week later and then trimmed to 31 for the World Cup following their last home test of the year against Tonga in Hamilton on September 7.